Transient field indicator

• US 4,825,152 A
• Filed: 04/22/1986
• Issued: 04/25/1989
• Est. Priority Date: 04/22/1986
• Status: Expired due to Fees

• Current Assignee: Pinion
• Original Assignee: Voyager Technologies, Inc. (Amphenol Corporation)
• Inventors: Bossard, Peter R.
• Primary Examiner(s): Smith, Jerry
• Assistant Examiner(s): Baker, Stephen M.
• Application Number:
  US06/855,074
• Time in Patent Office: 1,099 Days
• Field of Search: 324/102, 324/95, 324/96, 324/112, 324/113, 324/51, 324/72, 324/457, 324/260, 340/600, 340/662, 340/657, 340/659, 343/703, 250/475.2, 250/482.1, 250/250, 354/3, 346/335, 346/162, 346/163, 346/164, 346/150, 346/153.1, 346/74.2, 346/74.4, 355/3 R
• US Class Current: 324/95
• CPC Class Codes: G01R 13/04 for producing permanent records
• CPC Class Codes: G01R 13/14 Recording on a light-sensitive material
• CPC Class Codes: G01R 13/42 Instruments using length of spark discharge, e.g. by measuring maximum separation of electrodes to produce spark
• CPC Class Codes: G01R 29/0814 Field measurements related to measuring influence on or from apparatus, components or humans EMC, EMI and similar testing in general G01R31/001, e.g. in ESD, EMI, EMC, EMP testing, measuring radiation leakage; detecting presence of micro- or radiowave emitters; dosimetry; testing shielding; measurements related to lightning
• CPC Class Codes: G01R 33/02 Measuring direction or magnitude of magnetic fields or magnetic flux G01R33/20 takes precedence

Abstract

A photographic film is adapted to provide visual record of the occurrence of a transient electrostatic or transient magnetic field by the inclusion of metallic patterns close to the film. The patterns are of a geometry to define gaps at which the fields are concentrated in a manner to interact with the film. The film exhibits a light spot at the gap, when it is developed, if a field of sufficient intensity is present during the test period. The film packet is intended primarily for inclusion in the shipping package for sensitive electronic devices to provide a visual record of exposures during shipment.

Claims

1. In combination, a film and an antenna in energy coupling relationship with said film, said antenna having a geometry to define a gap and being responsive to the presence of a field to concentrate the energy of said field at said gap, said film being responsive to said concentrated energy at said gap to provide an indication thereof;

said film being an undeveloped photographic film and said antenna comprising first and second metallic depositions extending along said film and being closely spaced apart from one another in a manner to form a single gap therebetween;

wherein said field is electric and each of said first and second metallic depositions has a T-shape and the bases of the T-shapes are closely spaced apart to form said gap.

2. In combination, a film and an antenna in energy coupling relationship with said film, said antenna having a geometry to define a gap and being responsive to the presence of a field to concentrate the energy of said field at said gap, said film being responsive to said concentrated energy at said gap to provide an indication thereof;

said film being an undeveloped photographic film and said antenna comprising first and second metallic depositions extending along said film and being closely spaced apart from one another in a manner to form a single gap therebetween;

said field being electric and each of said first and second metallic depositions having a T-shape and the bases of the T-shapes being closely spaced apart to form said gap;

said first and second depositions being formed on opposite faces of said film.

3. A combination in accordance with claim 2 wherein said film has a covering layer and is adapted to self develop when said covering layer is removed.

4. A combination in accordance with claim 3 wherein said first and second metallic depositions are formed on the outward facing surfaces of said film.

5. In combination, a film and an antenna in energy coupling relationship with said film, said antenna having a geometry to define a gap and being responsive to the presence of a field to concentrate the energy of said field at said gap, said film being responsive to said concentrated energy at said gap to provide an indication thereof;

said film being an undeveloped photographic film and said antenna comprising first and second metallic depositions extending along said film and being closely spaced apart from one another in a manner to form a single gap therebetween;

further including an opaque envelope enclosing said film.

6. In combination, a film and an antenna in energy coupling relationship with said film, said antenna having a geometry to define a gap and being responsive to the presence of a field to concentrate the energy of said field at said gap, said film being responsive to said concentrated energy at said gap to provide an indication thereof;

said film being an undeveloped photographic film and said antenna comprising first and second metallic depositions extending along said film and being closely spaced apart from one another in a manner to form a single gap therebetween;

wherein said film has a covering layer and is adapted to self develop when said covering layer is removed.

7. In combination, a film and an antenna in energy coupling relationship with said film, said antenna having a geometry to define a gap and being responsive to the presence of a field to concentrate the energy of said field at said gap, said film being responsive to said concentrated energy at said gap to provide an indication thereof;

said film being an undeveloped photographic film and said antenna comprising first and second metallic depositions extending along said film and being closely spaced apart from one another in a manner to form a single gap therebetween;

wherein said field has an associated magnetic flux;

wherein said antenna comprises a metallic material having a geometry to define a gap for concentrating the energy associated with the magnetic flux; and

wherein said antenna has the shape of a loop, said loop having a segment missing for defining said gap.

8. In combination, a film and first and second antenna in energy coupling relationship with said film;

said first antenna comprising first and second metallic shapes spaced apart in a manner to form a first gap therebetween and being responsive to the occurrence of an electric discharge to concentrate the resulting electric field at said first gap;

said second antenna comprising a material responsive to the presence of a magnetic field, said second antenna having a geometry to form a second gap and being adapted to concentrate said magnetic field as a current at said second gap.